Technical Field
[0001] The present invention relates to a tear film stabilizing agent, a therapeutic agent
for corneal epithelial disorders, and a prophylactic agent, an ameliorating agent
and a therapeutic agent for meibomian gland dysfunction, as well as a prophylactic
agent, an ameliorating agent and a therapeutic agent for dry eye.
Background Art
[0002] Dry eye is a disease or symptom that develops into a chronic state with damage to
the cornea and conjunctiva on the surface of the eye, resulting in dryness, discomfort,
and visual function abnormalities due to abnormalities in the amount and composition
of tears based on various factors. It is said that people receive more than 80% of
their information through their eyes, and dry eye, which causes chronic eye symptoms,
restricts behavior, lowers motivation, and reduces QOL (Non-patent Document 1).
[0003] Dry eye is a highly prevalent disease or condition. In recent years, due to the spread
of air conditioning and the increase in VDT (visual display terminals) workers, etc.,
the number of dry eye patients has increased rapidly, reaching 8 million people in
Japan and over 90 million people worldwide, and there is a growing medical need. In
addition, it has been reported that the prevalence in Asia including Japan is higher
than in Europe and the United States.
[0004] Furthermore, it is anticipated the number of complainants due to aging, wearing of
contact lenses, and long hours of computer work, which are risk factors for dry eye,
will continue to increase in the future. It is said that the act of continuously looking
at a monitor screen makes it easier for tears to dry, causing eye strain and leading
to a decline in visual function called evening presbyopia. There is a wide range of
other causes for dry eye, and it is known to occur as a side effect of anticancer
drug treatment. In particular, anticancer drugs are thought to affect corneal cells
in which cell division is active, and dry eye is positioned as a side effect frequently
seen with many molecular targeted drugs (Non-patent Document 2).
[0005] In dry eye, it is said that deterioration of the tear film stability is one of the
core mechanisms, and corneal and conjunctival epithelial disorders become prominent
in the process of becoming chronic and severe, resulting in various subjective symptoms.
Dry eye is classified into the tear-deficient type and the evaporative type according
to its cause. Meibomian gland dysfunction (MGD) is considered to be the cause of the
evaporative type dry eye, and MGD is the cause in a significant proportion of patients
who visit ophthalmology with dry eye symptoms such as ocular discomfort (Non-patent
Document 1). In dry eye with a short tear film break-up time (BUT), characteristically
the tear film break-up time is shortened, but the tear secretion is normal and the
epithelial damage on the ocular surface is mild, considering that the subjective symptoms
are strong.
[0006] Destruction (destabilization) of the tear film is caused by an abnormality in the
tear lipid layer, a decrease in the water content of the tear film, an abnormality
in the secretory mucin, or a decrease in the wettability of the epithelium. Currently,
in Japan, the mainstream dry eye treatment is to compensate for the lack of ocular
surface components as the cause of the destruction of the tear film that induces dry
eye. Specifically, artificial tears, sodium hyaluronate ophthalmic solution, rebamipide,
diquafosol sodium, etc., which have an effect of promoting the secretion of mucin
on the ocular surface, are used. While these ingredients promote the production of
mucin and water and have the effect of stabilizing the tear film, it has been reported
that diquafosol sodium causes ocular discharge and eye pain, and rebamipide causes
dysgeusia as a side effect specific to ingredients. In addition, cyclosporine, which
is used for severe dry eye, has many side effects, and a safer and more effective
treatment for dry eye is desired.
[0007] The meibomian gland is a sebaceous gland that is located in the tarsal plate and
has openings on the upper and lower eyelid margins. Lipids secreted by the meibomian
gland are distributed in the eyelid margin and the outermost layer of the tear, and
they work to inhibit tear evaporation, promote tear stability, promote the spreading
of tears onto the ocular surface, suppress the outflow of tears at the eyelid margin
to the skin and such.
[0008] MGD is clinically used to describe a condition in which the meibomian gland function
is abnormal, and is thought to be one of the causes for the evaporative type dry eye,
but its definitions and diagnostic criteria are still unclear due to the wide range
of severity and diversity of clinical presentations. For these reasons, there are
few effective treatments to date.
[0009] As described above, dry eye is a chronic eye disease that forms a vicious cycle in
which corneal epithelial disorders and meibomian gland dysfunction influence and encourage
each other, with destabilization of the tear film as one of the core mechanisms. Although
stratified treatment of the ocular surface has been proposed to treat dry eye by increasing
the stability of the tear film through supplementing the deficient components of the
ocular surface, agents effective only in some layers are insufficient. There is a
need for therapeutic agents that are pleiotropically effective against the core mechanisms
of dry eye.
[0010] On the other hand, it has not been described or suggested that apocynin has a stabilizing
effect on the tear film, a therapeutic effect on corneal epithelial disorders, or
a therapeutic effect on meibomian gland dysfunction. Moreover, its action as a prophylactic
agent, an ameliorating agent or a therapeutic agent for dry eye is not known at all.
Citation List
Non-patent Documents
Summary of the Invention
Problems to be Solved by the Invention
[0012] The present invention has been made in view of the above circumstances, and an objective
of the present invention is to provide a prophylactic agent, an ameliorating agent,
or a therapeutic agent for dry eye that is excellent in the effect of stabilizing
tear film, effect of treating corneal epithelial disorders, and effect of treating
meibomian gland dysfunction.
Means for Solving the Problems
[0013] The present inventors have made intensive studies to achieve the above objective,
and they found that apocynin is excellent in the effect of stabilizing tear film,
effect of treating corneal epithelial disorders, and effect of treating meibomian
gland dysfunction, and is useful as a prophylactic agent, an ameliorating agent, or
a therapeutic agent for dry eye, and have thereby completed the present invention.
[0014] Therefore, the present invention provides the agents below.
Embodiment 1
[0015] A tear film stabilizing agent comprising apocynin.
Embodiment 2
[0016] A therapeutic agent for a corneal epithelial disorder comprising apocynin.
Embodiment 3
[0017] A therapeutic agent for meibomian gland dysfunction comprising apocynin.
Embodiment 4
[0018] A prophylactic agent, an ameliorating agent or a therapeutic agent for dry eye comprising
apocynin.
Embodiment 5
[0019] The agent according to any one of embodiments 1 to 3, which is a prophylactic agent,
an ameliorating agent or a therapeutic agent for dry eye.
Embodiment 6
[0020] The agent according to embodiment 4 or 5, which is a prophylactic agent, an ameliorating
agent or a therapeutic agent for tear-deficient type dry eye.
Embodiment 7
[0021] The agent according to embodiment 4 or 5, which is a prophylactic agent, an ameliorating
agent or a therapeutic agent for evaporative type dry eye.
Embodiment 8
[0022] The agent according to embodiment 4 or 5, which is a prophylactic agent, an ameliorating
agent or a therapeutic agent for short-BUT type dry eye.
Embodiment 9
[0023] The agent according to embodiment 1, which is a prophylactic agent, an ameliorating
agent or a therapeutic agent for a disease or symptom due to destabilization of the
tear film selected from the group consisting of diseases or symptoms of eye fatigue,
eye strain, eye dryness, blurred vision, eye pain, eye dazzles, heavy eye, eye discomfort,
ocular discharge, lacrimation, hypolacrimation , age-related dry eye, alacrima, dry
eye syndrome, Sjögren's syndrome, keratoconjunctivitis sicca, Stevens-Johnson syndrome,
ocular pemphigoid, blepharitis, insufficiency of eye closure, sensory nerve paralysis,
dry eye, tear-deficient type dry eye, evaporative type dry eye, short-BUT type dry
eye, dry eye associated with allergic conjunctivitis, dry eye post viral conjunctivitis,
dry eye post cataract surgery, dry eye associated with VDT work, dry eye associated
with long period of staring at monitor screen, and dry eye associated with wearing
contact lenses, as well as the group consisting of disorders or symptoms selected
from discomfort while wearing contact lenses, lid wiper epitheliopathy, corneal and
conjunctival epithelial disorders, corneal epithelial detachment, corneal epithelial
erosion, corneal ulcers and eye infections.
Embodiment 10
[0024] The agent according to embodiment 2, which is a prophylactic agent, ameliorating
agent or therapeutic agent for a disease or symptom due to a corneal epithelial disorder
selected from the group consisting of eye fatigue, eye strain, eye dryness, blurred
vision, eye pain, eye dazzles, heavy eye, eye discomfort, ocular discharge, lacrimation,
corneal ulcers, corneal epithelial detachment, corneal inflammation, dry eye, tear-deficient
type dry eye, evaporative type dry eye, short-BUT type dry eye, conjunctivitis, chronic
superficial keratitis, corneal erosion, drug-induced corneal damage, persistent corneal
damage, punctate superficial keratopathy , corneal epithelial defect, conjunctival
epithelial defect, keratoconjunctivitis sicca, superior limbic keratoconjunctivitis,
filamentary keratoconjunctivitis, infectious keratitis, non-infectious keratitis,
infectious conjunctivitis, non-infectious conjunctivitis, corneal scarring or corneal
scar formation as well as conjunctival scarring or conjunctival scar formation associated
with keratoconjunctival disorder.
Embodiment 11
[0025] The agent according to embodiment 3, which is a prophylactic agent, ameliorating
agent or therapeutic agent for a disease or symptom due to meibomian gland dysfunction
selected from the group consisting of eye fatigue, eye strain, eye dryness, blurred
vision, eye pain, eye dazzles, heavy eye, eye discomfort, burning sensation with hot
eyelids, ocular discharge, lacrimation, dry eye, tear-deficient type dry eye, evaporative
type dry eye, short-BUT type dry eye, meibomianitis, punctate superficial keratitis,
and blepharitis.
Embodiment 12
[0026] The agent according to any one of embodiments 1 to 11, which is an eye drop or an
eye ointment.
Embodiment 2-1
[0027] A method of stabilizing tear film, comprising administering a composition comprising
apocynin as an active ingredient to a subject in need of treatment.
Embodiment 2-2
[0028] A method of treating a corneal epithelial disorder, comprising administering a composition
comprising apocynin as an active ingredient to a subject in need of treatment.
Embodiment 2-3
[0029] A method of treating meibomian gland dysfunction, comprising administering a composition
comprising apocynin as an active ingredient to a subject in need of treatment.
Embodiment 2-4
[0030] A method of preventing, ameliorating or treating dry eye, comprising administering
a composition comprising apocynin as an active ingredient to a subject in need of
treatment.
Embodiment 2-5
[0031] The method according to any one of embodiments 2-1 to 2-3, which is a method for
preventing, ameliorating or treating dry eye.
Embodiment 2-6
[0032] The method according to embodiment 2-4 or 2-5, which is a method for preventing,
ameliorating or treating tear-deficient type dry eye.
Embodiment 2-7
[0033] The method according to embodiment 2-4 or 2-5, which is a method for preventing,
ameliorating or treating evaporative type dry eye.
Embodiment 2-8
[0034] The method according to embodiment 2-4 or 2-5, which is a method for preventing,
ameliorating or treating short-BUT type dry eye.
Embodiment 2-9
[0035] The method according to embodiment 2-1, which is a method for preventing, ameliorating
or treating a disease or symptom due to destabilization of the tear film selected
from the group consisting of diseases or symptoms of eye fatigue, eye strain, eye
dryness, blurred vision, eye pain, eye dazzles, heavy eye, eye discomfort, ocular
discharge, lacrimation, hypolacrimation , age-related dry eye, alacrima, dry eye syndrome,
Sjögren's syndrome, keratoconjunctivitis sicca, Stevens-Johnson syndrome, ocular pemphigoid,
blepharitis, insufficiency of eye closure, sensory nerve paralysis, dry eye, tear-deficient
type dry eye, evaporative type dry eye, short-BUT type dry eye, dry eye associated
with allergic conjunctivitis, dry eye post viral conjunctivitis, dry eye post cataract
surgery, dry eye associated with VDT work, dry eye associated with long period of
staring at monitor screen, and dry eye associated with wearing contact lenses, as
well as the group consisting of disorders or symptoms selected from discomfort while
wearing contact lenses, lid wiper epitheliopathy, corneal and conjunctival epithelial
disorders, corneal epithelial detachment, corneal epithelial erosion, corneal ulcers
and eye infections.
Embodiment 2-10
[0036] The method according to embodiment 2-2, which is a method for preventing, ameliorating
or treating a disease or symptom due to a corneal epithelial disorder selected from
the group consisting of eye fatigue, eye strain, eye dryness, blurred vision, eye
pain, eye dazzles, heavy eye, eye discomfort, ocular discharge, lacrimation, corneal
ulcers, corneal epithelial detachment, corneal inflammation, dry eye, tear-deficient
type dry eye, evaporative type dry eye, short-BUT type dry eye, conjunctivitis, chronic
superficial keratitis, corneal erosion, drug-induced corneal damage, persistent corneal
damage, punctate superficial keratopathy , corneal epithelial defect, conjunctival
epithelial defect, keratoconjunctivitis sicca, superior limbic keratoconjunctivitis,
filamentary keratoconjunctivitis, infectious keratitis, non-infectious keratitis,
infectious conjunctivitis, non-infectious conjunctivitis, corneal scarring or corneal
scar formation as well as conjunctival scarring or conjunctival scar formation associated
with keratoconjunctival disorder.
Embodiment 2-11
[0037] The method according to embodiment 2-3, which is a method for preventing, ameliorating
or treating a disease or symptom due to meibomian gland dysfunction selected from
the group consisting of eye fatigue, eye strain, eye dryness, blurred vision, eye
pain, eye dazzles, heavy eye, eye discomfort, burning sensation with hot eyelids,
ocular discharge, lacrimation, dry eye, tear-deficient type dry eye, evaporative type
dry eye, short-BUT type dry eye, meibomianitis, punctate superficial keratitis, and
blepharitis.
Embodiment 2-12
[0038] The method according to any one of embodiments 2-1 to 2-11, wherein the composition
is an eye drop or eye ointment.
Embodiment 3-1
[0039] A pharmaceutical composition for use in stabilizing tear film, comprising apocynin
as an active ingredient.
Embodiment 3-2
[0040] A pharmaceutical composition for use in treating a corneal epithelial disorder, comprising
apocynin as an active ingredient.
Embodiment 3-3
[0041] A pharmaceutical composition for use in treating meibomian gland dysfunction, comprising
apocynin as an active ingredient.
Embodiment 3-4
[0042] A pharmaceutical composition for use in preventing, ameliorating or preventing dry
eye, comprising apocynin as an active ingredient.
Embodiment 3-5
[0043] The pharmaceutical composition according to any one of embodiments 3-1 to 3-3, which
is for use in preventing, ameliorating or preventing dry eye.
Embodiment 3-6
[0044] The pharmaceutical composition according to embodiment 3-4 or 3-5, which is for use
in preventing, ameliorating or preventing tear-deficient type dry eye.
Embodiment 3-7
[0045] The pharmaceutical composition according to embodiment 3-4 or 3-5, which is for use
in preventing, ameliorating or preventing evaporative type dry eye.
Embodiment 3-8
[0046] The pharmaceutical composition according to embodiment 3-4 or 3-5, which is for use
in preventing, ameliorating or preventing dry eye.
Embodiment 3-9
[0047] The pharmaceutical composition according to embodiment 3-1, which is for use in preventing,
ameliorating or treating a disease or symptom due to destabilization of the tear film
selected from the group consisting of diseases or symptoms of eye fatigue, eye strain,
eye dryness, blurred vision, eye pain, eye dazzles, heavy eye, eye discomfort, ocular
discharge, lacrimation, hypolacrimation , age-related dry eye, alacrima, dry eye syndrome,
Sjögren's syndrome, keratoconjunctivitis sicca, Stevens-Johnson syndrome, ocular pemphigoid,
blepharitis, insufficiency of eye closure, sensory nerve paralysis, dry eye, tear-deficient
type dry eye, evaporative type dry eye, short-BUT type dry eye, dry eye associated
with allergic conjunctivitis, dry eye post viral conjunctivitis, dry eye post cataract
surgery, dry eye associated with VDT work, dry eye associated with long period of
staring at monitor screen, and dry eye associated with wearing contact lenses, as
well as the group consisting of disorders or symptoms selected from discomfort while
wearing contact lenses, lid wiper epitheliopathy, corneal and conjunctival epithelial
disorders, corneal epithelial detachment, corneal epithelial erosion, corneal ulcers
and eye infections.
Embodiment 3-10
[0048] The pharmaceutical composition according to embodiment 3-2, which is for use in preventing,
ameliorating or treating a disease or symptom due to a corneal epithelial disorder
selected from the group consisting of eye fatigue, eye strain, eye dryness, blurred
vision, eye pain, eye dazzles, heavy eye, eye discomfort, ocular discharge, lacrimation,
corneal ulcers, corneal epithelial detachment, corneal inflammation, dry eye, tear-deficient
type dry eye, evaporative type dry eye, short-BUT type dry eye, conjunctivitis, chronic
superficial keratitis, corneal erosion, drug-induced corneal damage, persistent corneal
damage, punctate superficial keratopathy , corneal epithelial defect, conjunctival
epithelial defect, keratoconjunctivitis sicca, superior limbic keratoconjunctivitis,
filamentary keratoconjunctivitis, infectious keratitis, non-infectious keratitis,
infectious conjunctivitis, non-infectious conjunctivitis, corneal scarring or corneal
scar formation as well as conjunctival scarring or conjunctival scar formation associated
with keratoconjunctival disorder.
Embodiment 3-11
[0049] The pharmaceutical composition according to embodiment 3-3, which is for use in preventing,
ameliorating or treating a disease or symptom due to meibomian gland dysfunction selected
from the group consisting of eye fatigue, eye strain, eye dryness, blurred vision,
eye pain, eye dazzles, heavy eye, eye discomfort, burning sensation with hot eyelids,
ocular discharge, lacrimation, dry eye, tear-deficient type dry eye, evaporative type
dry eye, short-BUT type dry eye, meibomianitis, punctate superficial keratitis, and
blepharitis.
Embodiment 3-12
[0050] The pharmaceutical composition according to any one of embodiments 3-1 to 3-11, wherein
the composition is an eye drop or eye ointment.
Effect of the Invention
[0051] According to the present invention, it is possible to provide tear film stabilizing
agents, corneal epithelial disorder treatment agents, and meibomian gland dysfunction
treatment agents that excel in the effect of stabilizing tear film, effect of treating
corneal epithelial disorders, and effect of treating meibomian gland dysfunction,
which are useful as prophylactic agents, ameliorating agents, or therapeutic agents
for dry eye.
Brief Description of the Drawings
[0052]
[Figure 1] It is a graph that demonstrates the results of tear film breakup time (BUT)
in the dry eye model of Example 1. All error bars in the graph indicate S.D. (standard
deviation).
[Figure 2] It is a graph showing Schirmer test results in the dry eye model of Example
1. All error bars in the graph indicate S.D.
[Figure 3A] It is a fluorescein-stained image of the dry eye model in Example 1.
[Figure 3B] It is a graph showing fluorescein staining scores in the dry eye model
of Example 1. All error bars in the graph indicate S.D.
[Figure 4A] It is a fluorescein-stained image of the dry eye model in Example 2.
[Figure 4B] It is a graph showing fluorescein staining scores in the dry eye model
of Example 2. All error bars in the graph indicate S.D.
[Figure 5] It is a graph showing the results of tear film breakup time (BUT) in the
dry eye model of Example 3. All error bars in the graph indicate S.D.
[Figure 6] It is a graph showing a fluorescein-stained image and staining scores in
the dry eye model of Example 3. All error bars in the graph indicate S.D.
[Figure 7A] It is a photographed image of an upper eyelid meibomian gland silhouette
in the dry eye model of Example 3.
[Figure 7B] It is a graph quantifying the meibomian gland area in the dry eye model
of Example 3. All error bars in the graph indicate S.D.
[Figure 8] It is a graph showing Schirmer test results in the dry eye model of Example
4. All error bars in the graph indicate S.D.
[Figure 9A] It is a graph showing fluorescein staining scores in the dry eye model
of Example 4. All error bars in the graph indicate S.D.
[Figure 9B] It is a graph showing fluorescein staining scores in the dry eye model
of Example 4. All error bars in the graph indicate S.D.
[Figure 10] It is a graph showing Schirmer test results in the dry eye model of Example
5. All error bars in the graph indicate S.D.
[Figure 11A] It is a graph showing fluorescein staining scores in the dry eye model
of Example 5. All error bars in the graph indicate S.D.
[Figure 11B] It is a graph showing fluorescein staining scores in the dry eye model
of Example 5. All error bars in the graph indicate S.D.
Mode for Carrying Out the Invention
[0053] Hereinbelow, the present invention will be explained in detail.
Apocynin
[0054] Apocynin is 4-hydroxy-3-methoxyacetophenone and has the formula below. Apocynin can
be produced by a known method, and commercially available products can also be used.

[0055] This product can be formulated as an ophthalmic drug comprising two or more active
ingredients by mixing other active ingredients and pharmaceutically acceptable additives
in addition to apocynin, using a commonly applied technique, or it can be formulated
as an ophthalmic drug comprising apocynin alone as an active ingredient by adding
a pharmaceutically acceptable additive to apocynin, using a commonly applied technique.
[0056] In the present invention, this drug is administered topically to the eye. Examples
of dosage forms of this drug include eye drop administration (including application
of eye ointment and eye wash), subconjunctival administration, intraconjunctival sac
administration, and subtenon administration, and eye drop administration is particularly
preferred.
[0057] The dosage form of this drug is not particularly limited as long as it is used for
topical administration to the eye. Examples include eye drops, eye ointments, injections,
patches, gels, and inserts. In addition, these can be prepared using the general techniques
widely used in the field.
[0058] Eye drops are prepared using isotonic agents such as sodium chloride, potassium chloride,
and concentrated glycerin; buffering agents such as sodium phosphate, sodium acetate
and epsilon-aminocaproic acid; surfactants such as polyoxyethylene sorbitan monooleate,
polyoxyl 40 stearate and polyoxyethylene hardened castor oil; stabilizers such as
sodium citrate and sodium edetate; and preservatives such as parabens, which are selected
for use as needed. The pH should be within the range acceptable for ophthalmic preparations,
but usually 4-8 is preferred.
[0059] Eye ointments can be prepared using commonly used bases such as white petrolatum
and liquid paraffin.
Other ingredients
[0060] The agents (compositions) of the present invention can contain an appropriate amount
of other ingredients within a range that does not impair the effects of the present
invention. Other ingredients include water, oily ingredients, surfactants, preservatives,
sugars, buffers, pH adjusters, isotonic agents, stabilizers, cooling agents, polyhydric
alcohols, thickeners, and such. These components can be blended singly or in combination
of two or more. The amount of water can be the remaining portion of the composition.
[0061] When the pharmaceutical composition of the present invention is an eye drop, the
content of the active ingredient apocynin is, for example, as a lower limit of at
least 0.00001% (w/v), at least 0.0001% (w/v), at least 0.001% (w/v)), at least 0.01%
(w/v), at least 0.003% (w/v), at least 0.03% (w/v), or at least 0.1% (w/v), and as
an upper limit of 1% (w/v) or less, 0.1% (w/v) or less, 0.03% (w/v) or less, 0.01%
(w/v) or less, 0.003% (w/v) or less, 0.001% (w/v) or less, or 0.0001% (w/v) or less.
The range is defined by any combination of these lower and upper limits, for example,
0.00001% (w/v) to 1% (w/v), 0.0001% (w/v) to 0.1% (w/v), 0.003% (w/v) to 0.03% (w/v),
0.003% (w/v) to 0.1% (w/v) or 0.001% (w/ v) to 0.01% (w/v). As one embodiment of the
present invention, the eye drop has an active ingredient content of 0.001% (w/v),
0.003% (w/v), 0.005% (w/v) or 0.01% (w/v), 0.03% (w/v), 0.1% (w/v). Note that "w/v"
represents weight/volume.
[0062] When used as an eye drop, it is applied preferably with 10 to 100 µL of 1 to 3 drops
at a time, 1 to 6 times a day, more preferably with 10 to 50 µL of 1 to 6 drops at
a time, 1 to 6 times a day, and even more preferably with 10 to 30 µL of 1 to 3 drops
at a time, 1 to 6 times a day. The administration method of the pharmaceutical composition
of the present invention may be appropriately determined according to the patient's
body weight, age, sex, degree of disease, and the like. In the case of eye drops,
the regimen in adults is, for example, 1 drop per eye, administered 1 to 6 times daily.
The administration interval can be determined appropriately, and for example, it can
be 3 to 4 hours.
[0063] The agent of the present invention can be suitably used as eye drops, eye drops for
contact lenses, eye washes, etc. From the point of view of its effectiveness in dry
eye prevention, amelioration or treatment, it can be suitably used as eye drops, eye
drops for contact lenses (eye drops for contact lens wearers) or other eye drops.
Contact lenses include hard contact lenses, soft contact lenses, silicone hydrogel
soft contact lenses, O2 hard contact lenses, color contact lenses, and others, and
are not particularly limited.
[0064] In addition, after filling the obtained agent (composition) in a resin container,
it is further sealed with a package, and an inert gas such as nitrogen is sealed in
the space formed between the above-mentioned container and the package. Alternatively,
after the composition is filled in a resin container, it may be sealed within a package
together with an oxygen scavenger.
[0065] This drug is intended to be administered to treat dry eye symptoms, but it may also
be locally administered to the eye prophylactically before dry eye symptoms develop.
[0066] One embodiment of the present invention relates to a method for treating, ameliorating,
or preventing dry eye and the diseases or symptoms described in the present disclosure,
comprising administering to a patient a composition comprising apocynin as an active
ingredient. Moreover, one embodiment of the present invention relates to the use of
apocynin in the treatment, amelioration or prevention of dry eye and the diseases
or conditions described in the present disclosure. In addition, one embodiment of
the present invention relates to the use of apocynin in the manufacture of a medicament
for the treatment, amelioration or prevention of dry eye and the diseases or conditions
described in the present disclosure.
Dry eye
[0067] Dry eye is defined as "a disease in which the stability of the tear film decreases
due to various factors, causing ocular discomfort and abnormal visual function, and
may be accompanied by damage to the ocular surface".
[0068] Dry eye is broadly classified into two types according to etiology: "tear-deficient
type" and "evaporative type" (Non-patent Document 1).
[0069] Tear-deficient dry eye reduces the production of tear fluid, damages the surface
of the eye, and causes symptoms such as constant dryness and foreign body sensation.
The causes include aging, stress, graft-versus-host disease (GVHD), Sjögren's syndrome,
tear secretion deficiency due to oral anticholinergic drugs, and lacrimal gland conduit
obstruction due to inflammatory ocular surface diseases such as Stevens-Johnson syndrome
or pemphigoid ophthalmicus, and impediment of the reflex tear pathway (reflex loop)
due to β-blockers, surgery, and such. Recently, a relationship between increased VDT
work hours and decreased lacrimal gland function has been reported, suggesting that
the living environment and lifestyle affect lacrimal secretion.
[0070] The causes of evaporative dry eye are classified into intrinsic and extrinsic factors.
Extrinsic factors include vitamin A deficiency, preservatives in eye drops (e.g.,
benzalkonium chloride), allergic conjunctivitis, use of contact lenses, and air conditioning.
Intrinsic factors include MGD, eyelid abnormalities such as rabbit eyes, and decreased
number of blinks.
[0071] In short-BUT dry eye, the BUT is shortened, lachrymal secretion is normal, and epithelial
damage on the ocular surface is mild, but severe symptoms are produced such as eye
fatigue, eye dryness, discomfort when wearing contact lenses, blurred vision, foreign
body sensation, eye pain, eye dazzles, heavy eye, eye discomfort, ocular discharge
and lacrimation. Conventionally used artificial tears and hyaluronic acid have poor
therapeutic effects.
[0072] In dry eye, when the stability of the tear film decreases due to various upstream
risk factors, corneal and conjunctival epithelial damage occurs due to drying stress,
resulting in damage to the mucin on the epithelial surface and reduced water wettability.
As a result, a vicious circle (core mechanism) occurs in which the stability of the
tear film is further reduced. Furthermore, this vicious circle results in inflammation,
which promotes epithelial damage. More recently, it has been proposed that symptoms
are caused by two mechanisms: a vicious circle of "decreased tear film stability"
when eyelids are kept open, and a vicious circle of "increased friction"' when blinking.
This is due to the stability of tear fluid, which prevents the ocular surface from
drying out, and its role as a lubricant to prevent excessive friction. As background
information, the vicious circle of "increased friction" during blinking is caused
by the interaction between the eyelid conjunctival epithelium and the ocular surface
epithelium (rubbing against each other via tear fluid) during blinking, resulting
in a decrease in the water content of the tear fluid and a decrease or qualitative
abnormality in secretory or membrane-type mucins. It is also known that meibomian
gland dysfunction (MGD) occurs in many patients with dry eye because the oils and
fats that come from the meibomian glands prevent tear evaporation. As described above,
dry eye is a chronic eye disease in which tear film instability is one of the core
mechanisms, and corneal epithelial disorder and meibomian gland dysfunction influence
and encourage each other, thereby forming a vicious circle, and this makes symptomatic
treatment alone by targeting inflammation or such insufficient.
[0073] Anti-inflammatory drugs such as corticosteroids and cyclosporin are used for treatment
of dry eye caused by collagen diseases related to autoimmunity such as Sjögren's syndrome.
Although corticosteroid eye drops have been proposed as a treatment option because
they improve subjective symptoms of dry eye, there is no evidence that they are effective
against tear stability. Although it is used infrequently, the possibility that it
may cause an increase in intraocular pressure and affect visual function cannot be
ruled out, and its use should be carefully monitored. There is no evidence that non-steroidal
anti-inflammatory drug (NSAID) eye drops are effective in improving subjective symptoms,
tear stability, or epithelial damage, while corneal hypersensitivity is sometimes
observed as an adverse event, and thus they are not practiced as a treatment option.
In addition, oral administration of common antioxidants and eye drops has not been
proven to be sufficiently effective for dry eye.
[0074] Dry eye is a chronic eye disease that may also involve systemic factors. Dry eye
associated with collagen disease is caused by autoimmune damage to the corneal conjunctival
epithelium, which leads to inflammation and destabilization of the tear film. On the
other hand, diabetic retinopathy and ischemic retinopathy are often associated with
the so-called lifestyle-related diseases such as diabetes, arteriosclerosis, and hypertension,
but because they are caused by ischemia in blood vessels, treatment such as retinal
photocoagulation is used, and little is known about their relationship to dry eye.
Dry eye also increases with age, but it is thought to have little association with
cataracts, glaucoma, retinal detachment, or other ocular diseases.
[0075] The outcome that should be considered in the treatment of dry eye patients with either
the tear-deficient type, the evaporative type, or the short-BUT type is the reduction
of subjective symptoms. These are prolongation of the break-up time (BUT), alleviation
of reduction of tear volume, and reduction of corneal epithelial damage.
[0076] The apocynin of the present invention elongates BUT, alleviates tear volume reduction,
and demonstrates a therapeutic effect on corneal epithelial disorders and a therapeutic
effect on meibomian gland dysfunction, based on its effect of stabilizing the tear
film. It can show remarkable prophylactic, ameliorating or therapeutic effects on
any types of dry eyes, whether it be the tear-deficient type, evaporative type, or
short-BUT type dry eye.
Tear film stabilizing agents
[0077] The present invention is a tear film stabilizing agent comprising apocynin, preferably
a tear film stabilizing agent comprising apocynin as an active ingredient.
[0078] In the present invention, the tear film stabilizing effect is measured by fluorescein
BUT or Schirmer test. Specifically, it is the method in the Example described below.
[0079] Once the stabilizing effect of the tear film is obtained, the agent can be suitably
used as a prophylactic, ameliorating, or therapeutic agent for dry eye, tear-deficient
type, evaporative type, or short-BUT type dry eye, in which instability of the tear
film is one of the core mechanisms. The tear film stabilizing agent of the present
invention may be used with or without an increase in the volume of tear secretion,
and even without an increase in tear secretion volume, it can show a remarkable prophylactic
or therapeutic effect for dry eye. Thus, one aspect of the present invention relates
to a prophylactic, ameliorating, or therapeutic agent for dry eye, for example, tear-deficient
type dry eye, evaporative type dry eye, and short-BUT type dry eye, comprising apocynin
as an active ingredient.
[0080] The following symptoms are listed as diseases or symptoms caused by destabilization
of the tear film, and the tear film stabilizing agent of the present invention can
be suitably used as a prophylactic agent, an ameliorating agent or a therapeutic agent
for the diseases or symptoms below.
[0081] Therefore, some aspects of the present invention are suitable for use as a prophylactic
agent, an ameliorating agent, or a therapeutic agent for the following diseases or
symptoms caused by tear film instability: eye fatigue, eye strain, eye dryness, blurred
vision, eye pain, eye dazzles, heavy eye, eye discomfort, ocular discharge, lacrimation,
hypolacrimation, age-related dry eye, alacrima, dry eye syndrome, Sjögren's syndrome,
keratoconjunctivitis sicca, Stevens-Johnson syndrome, ocular pemphigoid, blepharitis,
insufficiency of eye closure, sensory nerve paralysis, dry eye, tear-deficient type
dry eye, evaporative type dry eye, short-BUT type dry eye, dry eye associated with
allergic conjunctivitis, dry eye post viral conjunctivitis, dry eye post cataract
surgery, dry eye associated with VDT work, dry eye associated with long period of
staring at monitor screen such as smartphones and video games, and dry eye associated
with wearing contact lenses, as well as the group consisting of disorders or symptoms
selected from discomfort while wearing contact lenses, lid wiper epitheliopathy, corneal
and conjunctival epithelial disorders, corneal epithelial detachment, corneal epithelial
erosion, corneal ulcers and eye infections.
Therapeutic agents for corneal epithelial disorders
[0082] One aspect of the present invention is an agent for treating corneal epithelial disorders
comprising apocynin, and it is preferred that the agent is an agent for treating corneal
epithelial disorders comprising apocynin as an active ingredient.
[0083] In the present invention, the efficacy of corneal epithelial disorder treatment is
measured by the fluorescein-stained image of the eye surface and the fluorescein staining
score. Specifically, the method is described in the Example below.
[0084] Once a therapeutic effect on corneal epithelial damage is obtained, the product can
be suitably used as a prophylactic agent, an ameliorating agent, or a therapeutic
agent for dry eye.
[0085] The cornea is a transparent, avascular tissue with a diameter of about 1 cm that
covers the front surface of the eyeball, and the conjunctiva is the mucous membrane
that covers the surface of the eyeball behind the corneal limbus and the back surface
of the eyelid. They play important functions in vision, and any disturbance has serious
effects on visual function. Corneal and conjunctival disorders induced by dry eye
are caused by external obstruction, delayed repair of the obstruction or spreading
of the obstruction induced by some reasons. Since the cornea and conjunctiva are connected
tissues, these diseases adversely affect the normal architecture of each other's epithelium,
and they may even impair the structure and function of the corneal stroma and endothelium.
[0086] In dry eye, the corneal conjunctival epithelial damage becomes more pronounced as
the disease becomes chronic and severe, with a decrease in tear film stability as
one of the core mechanisms. Apocynin has an excellent therapeutic effect on the corneal
epithelium and is useful as a prophylactic agent, an ameliorating agent, and a therapeutic
agent for dry eye.
[0087] The drug-induced corneal epithelial disorder appears as a punctate superficial corneal
layer similar to dry eye. Causative eye drops include sympatholytics and nonsteroidal
anti-inflammatory drugs (NSAIDs), which reduce corneal sensitivity, and preservatives
in eye drops, particularly benzalkonium chloride. Systemic drugs such as anticancer
drugs, amiodarone, and isotretinoin also severely damage the cornea.
[0088] It has been reported that typical dry eye symptoms are actually induced by administering
these drugs to mice (Non-patent Documents 2 and 3).
[0089] In the present invention, a keratoconjunctival disorder refers to conditions in which
the cornea and conjunctiva are damaged due to various factors such as lacrimal abnormalities,
metabolic disorders, and external obstacles. Examples include corneal ulcers, corneal
epithelial detachment, corneal inflammation, dry eye, conjunctivitis, chronic superficial
keratitis, corneal erosion, drug-induced corneal damage, persistent corneal damage,
punctate superficial keratopathy , corneal epithelial defect, conjunctival epithelial
defect, keratoconjunctivitis sicca, superior limbic keratoconjunctivitis, filamentary
keratoconjunctivitis, infectious keratitis, non-infectious keratitis, infectious conjunctivitis,
and non-infectious conjunctivitis. Further, in the present invention, corneal scarring
(corneal scar formation) as well as conjunctival scarring (conjunctival scar formation)
associated with keratoconjunctival disorder are also examples of the keratoconjunctival
disorder.
Meibomian gland dysfunction therapeutic agent
[0090] One aspect of the present invention is a therapeutic agent for meibomian gland dysfunction
comprising apocynin. One aspect of the present invention is a therapeutic agent for
meibomian gland dysfunction comprising apocynin, preferably a therapeutic agent for
meibomian gland dysfunction comprising apocynin as an active ingredient.
[0091] In the present invention, the therapeutic effect of meibomian gland dysfunction is
determined based on the silhouette image of the meibomian glands. Specifically, the
method is in the Example described below.
[0092] The meibomian glands present in the eyelids secrete lipids and are important as the
source of supply for the lacrimal lipid layer. This tear lipid layer is important
for lowering the surface tension of tears, preventing evaporation of tears, and stabilizing
tears as a film. However, there are few reports on the secretory mechanism of the
meibomian glands, and it has not been fully elucidated.
[0093] In the present invention, MGD is a condition in which the function of the meibomian
glands is diffusely or locally abnormal due to various factors, and it is often accompanied
by dry eye symptoms such as abnormalities of the tear fluid and ocular surface, chronic
ocular discomfort (rattling, shaggy feeling, etc.). Symptoms of MGD include eye fatigue,
eye strain, eye dryness, blurred vision, eye pain, eye dazzles, heavy eye, eye discomfort,
burning sensation with hot eyelids, ocular discharge, lacrimation, and such. Furthermore,
MGD may be accompanied by inflammatory diseases, and such MGD is also suitable for
application of the present invention. The inflammatory diseases include, for example,
meibomianitis, punctate superficial keratitis, and blepharitis.
[0094] In the treatment of MGD, hyperthermia and compression by applying physical force
are performed to improve meibomian gland blockage. In recent years, methods have also
been developed in which the tear lipid layer is evaluated using interference images,
and the eyelid is treated from the inside using heat and massage effects. However,
since all these methods require treatment within a medical institution, a simple treatment
method is eagerly awaited.
[0095] MGD is broadly divided into the hyposecretory type and hypersecretory type, and the
hyposecretory type is more frequent in clinical practice. MGD of the hyposecretory
type are primary and can be obstructive, atrophic or congenital, with the obstructive
type being the most common. In the obstructive type, excess keratinized material accumulates
in the meibomian gland ducts, meibomian gland lipid secretion decreases, and atrophy
of the meibomian gland acini progresses gradually. Atrophic refers to primary atrophy
of the gland acini. In secondary atrophy, a variety of factors cause obstruction of
the meibomian gland orifices, resulting in a decrease in the secretion of meibomian
gland lipid. Contact lenses have also been reported to affect the morphology of meibomian
glands and contribute to dry eye.
[0096] As used in the present disclosure, atrophy of meibomian glands refers to a state
in which the volume of an organ or tissue that has grown to a normal volume has decreased
due to various factors, and it may include total or partial atrophy of meibomian glands.
As used in the present disclosure, atrophy of meibomian glands refers to atrophy of
any of the parts that make up the meibomian glands, such as (but not limited to) secretory
acini, small ducts, central ducts, and exit ducts, or a combination thereof. Examples
of meibomian atrophy with decreased meibomian gland volume include, but are not limited
to, atrophy due to shedding of glandular tissue, acinar loss, and decreased cell numbers.
In a preferred embodiment of the invention, the meibomian gland dysfunction is accompanied
by atrophy of the meibomian glands.
[0097] In other words, the agents used for specific medical uses described in the present
disclosure can also be expressed as pharmaceutical compositions for specific medical
uses, particularly for treatment of dry eye. Also, the agents or pharmaceutical compositions
described in the present disclosure may be used in methods, particularly methods of
treating dry eye, that include administering such compositions to a subject or patient
in need thereof.
[0098] Although preferred embodiments of the present invention have been described in the
present specification, it will be apparent to those skilled in the art that such embodiments
are provided for illustrative purposes only, and various modifications, changes and
substitutions could be made without departing from the invention by those skilled
in the art. One should understand that various alternative embodiments of the present
invention described herein may be used in practicing the invention. Further, it should
be interpreted that the contents of all publications, including patents and patent
applications, referenced herein are deemed to be incorporated by reference as if expressly
set forth herein.
[0099] Although the present invention will be described in detail below using examples,
the present invention is not limited to the examples below. In addition, the reagents
and materials used are commercially available unless otherwise specified.
Examples
Example 1: Therapeutic effects of apocynin on dry eye model animals
[0100] After acclimating male C57BL6 mice (7 weeks old) to the experimental environment,
those with almost uniform body weight values and no eye abnormalities were divided
into the following 3 groups (n = 5).
- 7 weeks old / normal (non-dry eye group)
- 7 weeks old / dry eye model + control (solvent eye drop) group
- 7 weeks old / dry eye model + apocynin eye drop group
[0101] The dry eye model was created by daily instillation of an EGF receptor inhibitor
(erlotinib) based on the method of Yang et al. In this model, administration of erlotinib
causes dry eye symptoms such as shortened BUT, decreased tear volume, and corneal
damage after 1 week of administration (Non-patent Document 3). After 20 pM of erlotinib
was instilled for 2 weeks, the control group received PBS alone, and the test group
received 3 µL of a suspension of 0.003% (w/v) apocynin in PBS twice daily. Two weeks
after the start of instillation, 1 pL of 0.1% sodium fluorescein solution was instilled
into each of both eyes under isoflurane anesthesia, and a BUT test was performed using
a slit lamp (Kowa Co., Ltd., SL-17) (Figure 1). In addition, the Schirmer test was
used to evaluate tear volume. Under anesthesia, the tip of a Schirmer test paper cut
to 1 mm width was inserted into the conjunctival sac of the lower eyelid of the mouse,
the test paper was removed after 5 minutes, the length of the wetted part was read
in units of 0.5 mm, and the value was used as the tear volume (Figure 2).
[0102] As shown in Figures 1 and 2, the apocynin eye drop group improved the shortening
of BUT and the reduction of tear volume in the dry eye model, demonstrating that apocynin
is useful as a tear film stabilizing agent.
Evaluation of therapeutic effects for corneal epithelial disorders
[0103] In the dry eye model prepared in Example 1, after BUT measurement, fluorescein-stained
images were photographed under a blue filter using a slit lamp (Kowa Co., Ltd., SL-17),
and corneal epithelial damage was analyzed (Figure 3). The lesioned area of the cornea
was stained by fluorescein staining. For the corneal damage score, the central part
of the mouse eye was taken as one area, and the other area was divided into four equivalent
regions, and each of the total five regions was scored from 0 to 3 points according
to the degree of staining (15 points in total).
[0104] As shown in Figure 3, significant improvement was observed in the apocynin eye drop
group for the corneal epithelial damage that occurred in the dry eye model of Example
1, demonstrating that apocynin is useful as a therapeutic agent for corneal epithelial
damage.
Example 2: Therapeutic effects of apocynin on the dry eye model animals
[0105] After acclimating male C57BL6 mice (9 weeks old) to the experimental environment,
those with almost uniform weight values and no eye abnormalities were divided into
the following 3 groups (n = 3).
- 7 weeks old / normal (non-dry eye group)
- 7 weeks old / dry eye model + control (solvent eye drop) group
- 7 weeks old / dry eye model + apocynin eye drop group
[0106] The dry eye model was created by instilling a 0.2% benzalkonium chloride solution
based on the method of Lin et al. (Non-patent Document 4). In this model, instillation
of the 0.2% benzalkonium chloride solution causes dry eye symptoms such as shortened
BUT, decreased tear volume, and corneal epithelial damage after 1 day of administration
(Non-patent Document 4). After the benzalkonium chloride solution was instilled twice
daily for 2 days, PBS alone was administered to the control group, and for the test
group, a solution of apocynin 0.003% (w/v) suspended in PBS was administered to both
eyes at 3 µL each, 4 times daily. Two days after the start of apocynin instillation,
1 pL of 0.1% fluorescein sodium solution was instilled into each of both eyes under
isoflurane anesthesia, and stained images were taken under a blue filter using a slit
lamp (Kowa Co., Ltd., SL-17). The fluorescein staining scores were analyzed (Figure
4).
[0107] As shown in Figure 4, corneal epithelial damage induced by the benzalkonium chloride
solution was significantly improved in the apocynin eye drop group, and it was demonstrated
that apocynin is also useful as a therapeutic agent for corneal epithelial damage
in dry eye models induced by different drugs.
Example 3: Therapeutic effects of apocynin on dry eye model animals
[0108] After acclimating male C57BL6 mice (7 weeks old) to the experimental environment,
those with almost uniform body weight values and no eye abnormalities were divided
into the following 3 groups (n = 4).
- 7 weeks old / normal (non-dry eye group)
- 7 weeks old / dry eye model + control (solvent eye drop) group
- 7 weeks old / dry eye model + apocynin eye drop group
[0109] The dry eye model was prepared by dissolving erlotinib at a concentration of 5 mg/ml
in 0.5% methylcellulose solution and administering it by intraperitoneal injection
at a concentration of 50 mg/kg/day daily from the start of the study. The solvent
0.5% methylcellulose solution was similarly administered to the normal non-administration
group. After one week of administration of erlotinib, the control group received PBS
alone, and the test group received a solution of 0.003% (w/v) apocynin suspended in
PBS twice a day at both eyes with 3 µL each. One week after the start of instillation,
1 pL of 0.1% sodium fluorescein solution was instilled into each of both eyes under
isoflurane anesthesia, and the BUT test was performed under a blue filter using a
slit lamp (Kowa Co., Ltd., SL-17) (Figure 5).
[0110] As shown in Figure 5, BUT, which was significantly reduced by the systemic administration
of erlotinib in the dry eye model, was significantly improved by instillation of apocynin,
indicating that apocynin is useful as a tear film stabilizing agent.
[0111] In Example 3, one week after the start of apocynin instillation, photographs were
taken under isoflurane anesthesia, and the degree of corneal damage was scored (Figure
6).
[0112] As shown in Figure 6, corneal epithelial damage induced by systemic administration
of erlotinib was significantly improved in the apocynin eye drop group, and it was
shown that apocynin is useful as a therapeutic agent also for corneal epithelial damage
in dry eye models induced by systemic drugs.
Evaluation of therapeutic effects on meibomian gland dysfunction
[0113] The mice used in Example 3 were sacrificed 2 weeks after the start of apocynin instillation,
the skin and conjunctival epithelium of the upper eyelids were removed, and the silhouette
of the meibomian glands was observed and photographed using a transmitted light source
under a stereoscopic microscope. Figure 7A shows a silhouette image of the upper eyelid
taken from a dry eye model mouse. The areas that looked like dark shadows of trees
were all meibomian glands. In addition, the image analysis software Imaged was used
to quantify the area of the meibomian gland silhouette image of the upper eyelid image
(Figure 7).
[0114] As shown in Figure 7, comparison of the silhouettes of the meibomian glands showed
that some meibomian glands were missing in the dry eye model, and it was confirmed
that the instillation of apocynin reduced the missing parts. Quantification of the
meibomian gland silhouette area at this time revealed that apocynin significantly
inhibits atrophy of the meibomian glands.
[0115] Therefore, it was shown that apocynin has the effect of improving the atrophy of
the meibomian glands and is useful as a therapeutic agent for meibomian dysfunction.
Example 4: Therapeutic effects of apocynin on dry eye model animals
(comparative study 1)
[0116] After acclimating male C57BL6 mice (7 weeks old) to the experimental environment,
those with almost uniform weight values and no eye abnormalities were divided into
the following groups (n = 4).
- 7 weeks old / normal (non-dry eye group)
- 7 weeks old / dry eye model + control (solvent eye drop) group
- 7 weeks old / dry eye model + 0.1% (w/v) apocynin eye drop group
- 7 weeks old / dry eye model + 0.5% (w/v) hyaluronic acid eye drop group
[0117] A dry eye model was prepared by instilling the benzalkonium chloride solution at
3 pL each eye, twice a day for 8 days. After that, the control group received the
0.5% methylcellulose solution alone, and the test group received 0.1% (w/v) apocynin
or 0.5% (w/v) hyaluronic acid suspended in the 0.5% methylcellulose solution twice
a day for 15 days at 3 pL for each of both eyes.
[0118] Schirmer's test was performed 1, 3, 6, and 8 days after the start of instillation
of the comparative test drug, and tear volume was evaluated.
[0119] As shown in Figure 8, in the dry eye model of Example 4, the control group showed
a marked decrease in tear volume compared to the normal group. The apocynin eye drop
group showed marked improvement in the tear volume compared to the hyaluronic acid
eye drop group 3 days after the start of eye drop instillation. This suggests that
apocynin is more effective than hyaluronic acid as a tear film stabilizer.
[0120] In Example 4, 1, 3, 6, 8, and 15 days after the start of instillation of the comparative
test drug, 1 pL of the 0.1% fluorescein sodium solution was instilled into each of
both eyes. Fluorescein-stained images were observed under a blue filter using a slit
lamp (Kowa Co., Ltd., SL-17), and the degree of corneal epithelial damage was scored.
[0121] As shown in Figure 9A, in the dry eye model of Example 4, the fluorescein staining
score was significantly increased in the control group compared to the normal group,
and corneal epithelial damage was observed. As shown in Figure 9A, in the apocynin
eye drop group, the fluorescein staining score was significantly reduced and the corneal
damage was improved 3 days after the start of eye drop instillation compared to the
control. On the other hand, no effect was observed in the hyaluronic acid eye drop
group. Furthermore, as shown in Figure 9B, in the apocynin eye drop group, a significant
decrease in the fluorescein staining score was observed even 15 days after the start
of eye drop instillation. From the above, apocynin has been shown to be more effective
than hyaluronic acid as a therapeutic agent for corneal epithelial disorders.
Example 5: Therapeutic effects of apocynin on dry eye model animals
(comparative study 2)
[0122] After acclimating male C57BL6 mice (7 weeks old) to the experimental environment,
those with almost uniform weight values and no eye abnormalities were divided into
the following groups (n = 3 to 4).
- 7 weeks old / normal (non-dry eye group)
- 7 weeks old / dry eye model + control (solvent eye drop) group
- 7 weeks old / dry eye model + 0.003% (w/v) apocynin eye drop group
- 7 weeks old / dry eye model + 0.03% (w/v) apocynin eye drop group
- 7 weeks old / dry eye model + 3% diquafosol sodium eye drop group
- 7 weeks old / dry eye model + 0.5% (w/v) hyaluronic acid eye drop group
[0123] A dry eye model was created by instilling 3 pL of the 0.2% benzalkonium chloride
solution into each of both eyes twice a day for 8 days. Then, the control group received
PBS alone, and the test group received 0.003% (w/v), 0.03% (w/v) apocynin and 0.5%
(w/v) hyaluronic acid in PBS. The 3% diquafosol sodium eye drop was instilled into
each of both eyes at 3 pL, twice a day for 9 days.
[0124] Two days after the start of instillation of the comparative test drug, the Schirmer
test was performed to evaluate the tear volume.
[0125] As shown in Figure 10, in the dry eye model of Example 5, the control group showed
a marked decrease in tear volume compared to the normal group. On the other hand,
as shown in Figure 10, in the 0.003% and 0.03% apocynin eye drop groups, 2 days after
the start of eye drop instillation, tear volume was significantly improved compared
to the hyaluronic acid eye drop group and the diquafosol sodium eye drop group. These
results showed that apocynin is more effective than hyaluronic acid and diquafosol
sodium as a tear film stabilizing agent.
[0126] In Example 5, 1, 2, 5, and 9 days after the start of instillation of the comparative
test drug, 1 pL of 0.1% sodium fluorescein solution was instilled into each of both
eyes. Fluorescein-stained images were observed under a blue filter using a slit lamp
(Kowa Co., Ltd., SL-17), and the degree of corneal epithelial damage was scored.
[0127] As shown in Figure 11A, in the dry eye model of Example 5, the fluorescein staining
score was significantly increased in the control group compared to the normal group,
and corneal epithelial damage was observed. On the other hand, in the 0.03% apocynin
eye drop group, the fluorescein staining score decreased significantly compared with
the control group two days after the start of eye drop instillation, and amelioration
of the corneal epithelial damage was observed. On the other hand, no effect was observed
in the hyaluronic acid eye drop group and the diquafosol sodium eye drop group. Furthermore,
as shown in Figure 11B, 9 days after the start of instillation, the 0.003% apocynin
and 0.03% apocynin eye drop groups significantly improved the fluorescein staining
scores compared to the control group, the hyaluronic acid eye drop group, and the
diquafosol sodium eye drop group. From the above, it was shown that apocynin is more
effective than hyaluronic acid and diquafosol sodium as a therapeutic agent for corneal
epithelial disorders.
[0128] In all types of dry eyes, whether the tear-deficient type, evaporative type, or short-BUT
type, the primary outcomes of treatment are stabilization of the tear film (improvement
of BUT shortening and tear fluid reduction) and reduction of corneal epithelial damage.
In addition, improvement of the meibomian gland dysfunction leads to improvement of
MGD which occurs in a significant proportion of dry eyes.
[0129] As shown in Examples 1 to 5, the apocynin of the present invention has a stabilizing
effect on the tear film, a therapeutic effect on corneal epithelial damage, and a
therapeutic effect on meibomian gland dysfunction, and has a remarkable prophylactic,
ameliorating, or therapeutic effect on dry eyes of any of the tear-deficient type,
evaporative type, and short-BUT type.
Industrial Applicability
[0130] The therapeutic agent of the present invention, which has apocynin as an active ingredient,
has been found to have a stabilizing effect on the tear film, a therapeutic effect
on corneal epithelial disorders, and a therapeutic effect on meibomian gland dysfunction.
Therefore, the present invention is useful as a prophylactic agent, an ameliorating
agent or a therapeutic agent for dry eye.